1. Field of the Invention
This application relates to a test set-up and a test method for non-destructive detection of a flaw in a device by means of an eddy current testing.
2. Description of Related Art
In a test set-up, an electromagnetic signal is produced in the device being tested that has an electrical conductivity. Eddy currents form in the device being tested and are picked up. Changes in these eddy currents around the flaw are analyzed.
International Patent Application Publication WO 2006/007826 A1 describes a device for non-destructive and contact-free detection of flaws in a device under test. In this case, a probe signal is scanned by means of an analog-digital-converter stage to form a demodulated digital measuring signal from the digitalized signal. The analog-digital-converter stage is triggered with a whole fraction of a frequency of a carrier oscillation.
UK Patent Application Publication GB 2 457 496 A deals with a system for detection of defects by means of eddy currents. A driver signal generates eddy currents in a test object. A measuring signal is digitalized by means of an analog-digital converter and then demodulated. Four or eight signal values are digitalized and demodulated per period of the measuring signal.